/**
 * @Auther: wangliuyang
 * @Date: 2021/4/19 22:25
 * @Description: 合并两个有序链表
 */
public class Solution_21 {

    public ListNode mergeTwoLists(ListNode l1, ListNode l2) {
        if (l1 == null) {
            return l2;
        }
        if (l2 == null) {
            return l1;
        }
        if (l2.val < l1.val) {
            l2.next = mergeTwoLists(l1, l2.next);
            return l2;
        } else {
            l1.next = mergeTwoLists(l1.next, l2);
            return l1;
        }
    }
}

